TY - JOUR
T1 - Sensitivity of bronchoprovocation and tracheal mucous velocity in detecting airway responses to O3
AU - Abraham, W. M.
AU - Januszkiewicz, A. J.
AU - Mingle, M.
AU - Welker, M.
AU - Wanner, A.
AU - Sackner, M. A.
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 1980
Y1 - 1980
N2 - This study was undertaken to determine whether measurements of tracheal mucous velocity or airway reactivity to inhaled carbachol more sensitively detect airway effects of inhaled ozone (O 3) in conscious sheep. Dose-response curves of mean pulmonary flow resistance (RL) to carbachol were obtained by measuring RL after five breaths of carbachol aerosol with stepwise increases in drug concentration. The animals then breathed 0.5 ppm O 3 through an endotracheal tube for 2 h. The dose-response curves were repeated immediately after the 0.5 ppm O 3 exposure and 24 h later. In the eight sheep studied, there were no significant alterations in base-line RL immediately after or 24 h after 0.5 ppm O 3. Airway hyperreactivity was not apparent immediately after the sheep breathed 0.5 ppm O 3, but it was evident 24 h later. In contrast, six sheep that breathed 0.5 ppm O 3 in the same manner for 2 h did not show a significant depression in tracheal mucous velocity the same day or 24 h later. Exposure to 1 ppm O 3 for 2 h resulted in airway hyperreactivity immediately after the exposure and elevated base-line RL 24 h later, 2 ppm O 3 produced an increase in base-line RL immediately after exposure. We conclude that, in conscious sheep, airway hyperreactivity appears to be a more sensitive indicator of airway effects produced by short-term exposure to 0.5 ppm O 3 than depression of tracheal mucous velocity.
AB - This study was undertaken to determine whether measurements of tracheal mucous velocity or airway reactivity to inhaled carbachol more sensitively detect airway effects of inhaled ozone (O 3) in conscious sheep. Dose-response curves of mean pulmonary flow resistance (RL) to carbachol were obtained by measuring RL after five breaths of carbachol aerosol with stepwise increases in drug concentration. The animals then breathed 0.5 ppm O 3 through an endotracheal tube for 2 h. The dose-response curves were repeated immediately after the 0.5 ppm O 3 exposure and 24 h later. In the eight sheep studied, there were no significant alterations in base-line RL immediately after or 24 h after 0.5 ppm O 3. Airway hyperreactivity was not apparent immediately after the sheep breathed 0.5 ppm O 3, but it was evident 24 h later. In contrast, six sheep that breathed 0.5 ppm O 3 in the same manner for 2 h did not show a significant depression in tracheal mucous velocity the same day or 24 h later. Exposure to 1 ppm O 3 for 2 h resulted in airway hyperreactivity immediately after the exposure and elevated base-line RL 24 h later, 2 ppm O 3 produced an increase in base-line RL immediately after exposure. We conclude that, in conscious sheep, airway hyperreactivity appears to be a more sensitive indicator of airway effects produced by short-term exposure to 0.5 ppm O 3 than depression of tracheal mucous velocity.
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U2 - 10.1152/jappl.1980.48.5.789
DO - 10.1152/jappl.1980.48.5.789
M3 - Article
C2 - 7451287
AN - SCOPUS:0018827588
VL - 48
SP - 789
EP - 793
JO - Journal of Applied Physiology
JF - Journal of Applied Physiology
SN - 8750-7587
IS - 5
ER -